NGC 1052 1:1 Merger Simulations Produce Long-Lived Tidal Dwarfs Matching Observed DM-Free Galaxies

The arXiv preprint reports hydrodynamical simulations of a major merger that reproduces NGC 1052's observed morphology while ejecting long-lived tidal features containing bound stellar systems. These TDGs reach sizes comparable to the NGC 1052 dwarfs, whereas the alternative head-on dwarf collision produces objects an order of magnitude smaller. The work directly tests whether hierarchical merging, rather than rare dwarf-dwarf collisions, accounts for the apparent absence of dark matter.

Existing observations of NGC 1052's outskirts already show extended tidal shells and streams consistent with the simulated remnant. The missing-satellites tension is eased because the same merger physics that builds massive ellipticals naturally populates their neighborhoods with TDGs whose baryon-dominated kinematics mimic DM-free galaxies. Radial distances between the dwarfs remain the decisive observable.

Current data cannot yet separate the two formation channels because projected positions alone are degenerate. Higher-resolution simulations are required to track globular-cluster formation, which the present runs cannot resolve. JWST proper-motion or line-of-sight velocity measurements at 50-100 kpc projected radius would falsify one scenario within three years.